Door closer



June 1, 1948. c. s. ASPENWALL DOOR CLOSER 2 Sheets-Sheep 1 Filed Aug. 20, 1945 June 1, 1948. c. s. ASPENWALL DOOR CLOSER 2 Sheets-Sheet 2 Filed Aug. 20, 1945 Patented June 1, 1948 UNITE STATE-HS Tear Price 5110.013 CLOSER :Anplication; August-20, 1945,5Serial No; 611,500

'.Z.This.;invention .relatesito an improved door closer, and has 'for one of its. principalobjects the :provision of a device whereloydoors can be closed automatically and without. slamming and wherein this vclosing can .be. accomplished. more eificien'tly.thanheretofore.

'..'One .of. the important objects or. this invention is to providea door closing device which .isof the lhydraulic ..style and which will .comprise a pair -ofpistons. as distinguished from the usual single piston. apparatus.

Another. importantobject or" the-invention is to provide a door closer-having apairrofpistons Operating on a. commoncrank shaft, which crankshaft'is offsetso that any possibility .of avdead centerlisjellminated.

(Another .andiiurther. important object -of the invention is .to .providei-n. a QdoorQolOser of the hydraulic type asingle valve whereby the :flow dflliquid T from two cylinders. :may 'be' controlled and. regulated. simultaneously.

lhnotherobiectisthe provision, in a door. closer, oflmeans'for decelerating .the;speed .of the closingldoonfrom 'thelinoeption of its closingmotion.

.Qther and 'furtherimportant .objects of the invention will be apparentlfrom the disclosures in the. accompanyingwdrawingsrand following specification.

l'lhelinventiomina preferred form,- is shownin the drawings =arid1hereinafter more fully .described.

.Inthe drawings:

I l-Figure .1 is a perspectiveview .ofthe improved door .-closer .of thisninvention, showing a preferred iorm.

-Flguregzis a sectional view: of the device taken on the line 2-4 of Figure3.

Figure 3'iswa vertical sectional View oi theapparatusitaken on the line 3-3of Figure-4,1001:- mg.- inthe direction indicated (by the arrows.

,-Eigur.e-,4 is-an endview of the-door closer, certaintinteriorspartsbeing shown in dotted lines.

-F.i ur.e 5 isasectional view'taken on the line liiof Figure A, looking-in the direction indicated.

figure. Gris-.a-section-on the broken line 6----t of Fi ure-5.

"Figure-'7 is'a section ontthe-line 'li-of Figure 5.

aAs: showneinlthe drawings "The. reference numeral -'l I] indicates the main bo'dyportionof the improved door closer of this inven'tionjthe same being flanked 'bytwo cylinders" IT'an'd l4', pr'eferably:integrarwith-the main body portion" Hi. It will-benoted "from-Figures 1 and3 that the .cylin'ders are offsetianddonot have.acommoriilongitudinal axis. Thisis mainly for the purpose of employing two jpistons in the respective cylinders, which. pistons operate one single crankshaft.

One of. these .pistons,.nainely',= ihatif or the cylinder i2, .is..indicated...at ii 5 .and'the piston for the cylinderM is. indicated .at H3.

"Each piston is ,joinedflby means of respective connecting rods '28 and 22 to ,asingle ,crakn fi l. Asbest shown in Figure .2, the prank 124 base throwpn one sideoii2il5sdegreesand onnthe other side. of .155 degrees, so that/there Willlbe ;n o dead center. so long as the, pistonsare, inrmotion. This ofiset of the orankshalftcanhe variedl'considerably Within effective Working :limit's from the 205% ratio lw'heneverisuoh variation is gJdesirable.

The crank L24. is ,mounted in suitable hearings in the body portion Iii, and its upperefidmmjectsbeyond the .top face of said bodyportion, this upper. end .terminatin iin a square shaft to which ,is lattachedone. end .of an adjustable arm 26 and ,to .thejother, end of this arm ,26'is: attached theouter endof anotheradjustable armf28,i .the innerend of which is adapteditobe aifixed tothe door. .irame or theliketfi. ".Theadjustable main arm 26 enables, lengthening or shortening'ofithe same .in .order to increase or decrease spring power by means ofa change of leverage, andalso to govern the shaft revolution 'toflaccoinplish :a hold-open'feature for the door hy passing adead center on .thecrank.

I As .Willbe notedfrom the drawings, 8, 2. Piston ifiand l8 surmounts a helical'sprin ,j these springs being shown at"32 andii'respectivelyand being positioned. inside thecylinders" l 2 audit respectively. "The. inner ends of'the,springsare;positioned-against inwardly projecting annular ledges of M the respective cylinders; so' that the springs Will .have a tendency. to "force the-pistons :Qutwardly atlall times.

Each .piston .isprovided with a ball valve 'as shown at "45 "and '..-the' cylinders themselves, -.together with thefi-bndy portion, are .filled .witha hydraulic liquid. 7

A tapered slot 42 is out into the side of each cylinder, as .best shown .in Figure 2, and it will be noted that the'largerend of ,each of thesetapered slots is'toward .the rear of the cylinder.

A passageway li leads from the end of each cylinder and this joins a 'duct- 56inthe body H], which-duct-extends par-allel tothe cylindersand are joined Joy an offset duct flifl in the r'bodyzi El, and this passageway is controlled by a needlevalve 3 50, which constitutes the only adjustment for the flow of hydraulic liquid through the apparatus. The needle valve 50 is mounted in a packing gland 52.

In operation, the device is full of a suitable hydraulic liquid and upon the opening of the door 54, the action of the arms 26 and 28, together with the crank 24, retracts the pistons 16 and I8 compressing the springs 32 and 34.

At the same time liquid goes past the ball valve 49 in the pistons I6 and 18.

Upon release of the opening force against the door, the springs 32 and 34 tend to force the pistons outwardly in the cylinders, accordingly imparting a closing movement to the door. The initial controlled closing motion of the door is relatively fast, owing to the fact that the larger portions of the tapered slots 42 are toward the rear of the cylinders and considerable hydraulic fluid is allowed to pass around the pistons during this first part of their motion outwardly.

As the pistons near the outward end of their travel, the taper of the slot restricts more and more the passage of liquid around the pistons and accordingly liquid must then be pushed through the passages 44 and 46 past the needle valve 50. Oviously, control of the passages by means of the needle valve will very accurately govern the speed of the closing movement of the door and allow the same to close in a fashion most to be desired.

The ofisetting of the cylinders allows the use of a double throw crank, and the fact that the crank itself is in a 155 degree to 205 degree ratio eliminates a mechanical dead center, inasmuch as one piston is opposed to the other so that when one is on dead center, the opposite piston is in motion when the crank shaft is in the act of revolving about its center. This also provides for constant pressure so far as the hydraulic action is concerned.

The primary control of the pistons is through the tapered slot, and the small end of the slot comprises the end of the first control. This still leaves sufficient liquid for port and valve control.

The use of a single needle valve or adjusting screw which adjusts the flow of liquid from the ends of both cylinders and through a common orifice leading the liquid to a point behind the pistons comprises an important feature of the invention. Obviously, the liquid in the body It), when the pistons are moving outwardly, is not under compression.

The ratio of the crankshaft offset can be varied within working limits to quite a departure from the 155205 relationship, so long as. a dead center construction is avoided.

It will be seen that herein is provided a new and improved door closer which, while being composed of a minimum of parts, is considerably more efiicient than those heretofore in use and which even comprise a greater number of moving parts. The offset crank whereby a mechanical dead center is eliminated, is an important new feature and the single regulating valve to control the motion of two pistons simultaneously will, it is believed, constitute a considerable advance in this art.

I am aware that many changes may be made and numerous details of construction varied throughout a wide range without departing from the principles of this invention, and I, therefore, do not propose limiting the patent granted hereon otherwise than as necessitated by the prior art.

I claim as my invention:

1. A door closer comprising a body, a pair of cylinders on the body, a piston in each cylinder, a spring behind each piston, tending to force the same normally outwardly, a supply of hydraulic fluid in the body and cylinders, a single regulating valve for fluid control, a crankshaft in the body and connecting rods between the crankshaft and the pistons, the crank being offset at approximately 205 degrees to degrees relative to its circumferential path of travel.

2. A door closer comprising a body, a pair of non-aligned cylinders on the body, a piston in each cylinder, a spring behind each piston, tending to force the same normally outwardly, a

supply of hydraulic fluid in the body and cylinders, a single regulating valve in the body for fluid control, a crankshaft in the body, connecting rods between the crankshaft and the pistons, the crank being oifset, a telescopic arm mounted on the outer end of the crankshaft, and a further arm connecting the outer end of the telescopic arm to a door frame, the door closer body being mounted on a door.

3. In a door closer, a body, a crankshaft mounted in the body, a pair of opposed cylinders positioned on the body in non-aligned relationship, a piston movable in each cylinder, a connecting rod between each piston and the respective portion of the crankshaft, a ball valve in each piston, a spring behind each piston, a duct leading from the outer end of each cylinder back to the body portion, hydraulic fluid in the body, cylinders and ducts, and a single regulating valve for control of the liquid flow.

4. A door closer including a body, a pair of opposed cylinders on the body, a piston in each cylinder, a crankshaft for the pistons in the body, a spring behind each piston tending to force the same normally outwardly, ducts connecting the outer ends of the cylinders with the body, a supply of hydraulic fluid in the body, ducts and cylinders, a single regulating valve in one of the ducts, and a tapered slot in each cylinder wall, the small end of each slot being adjacent the outer end of each cylinder.

5. A door closer including a body, a pair of opposed non-aligned cylinders on the body, a piston in each cylinder, a crankshaft for the pistons in the body, a spring behind each piston tending to force the same normally outwardly, a supply of hydraulic fluid in the body and cylinders, ducts connecting the outer ends of the cylinders with the body, a single regulating valve in one of the ducts, and a tapered slot in each cylinder wall, the small end of each slot being adjacent the outer end of each cylinder for decelerated outward piston movement.

6. A door closer including a body, a pair of cylinders onthe body, a piston in each cylinder, a crankshaft for the pistons in the body, a spring behind each piston tending to force the same normally outwardly, ducts connecting the outer ends of the cylinders with the body, a supply of hydraulic fluid in'the body ducts and cylinders, a single regulating valve in one of the ducts, a tapered slot in each cylinder-wall, the small and of each slot being adjacent the outer end of each cylinder for decelerated outward piston movement, and a pair of linked arms on the outer end of the crankshaft.

7. A door closer. including a body, a pair of opposed cylinders on the body, a piston in each cylinder, at crankshaft for the pistons in the body, a spring behind each piston tending to force the same normally outwardly, a supply of hydraulic fluid in the body and cylinders, ducts REFERENCES CITED connecting the outer ends of the cylinders w1th t bgdy a single regulating valve i one of The following references are of record 1n the the ducts, and a tapered slot in each cylinder file Of this patent! Wall, the small end of each slot being adjacent 5 UNITED STATES PATENTS the outer end of each cylinder for decelerated piston movement, the cylinders being nongg g C Name 0 aligned with respect to each other, and the 654,303 3; 33 1900 igg g gg fi appmxlmately a zos'degree- 10 766,387 Rixson Aug. 2, 1904 egree 8 810,411 Henry Jan. 23, 1906 CARL S. AS PENWALL. 2,159,067 Weiser May 23, 1939 

